Clamping device



Dec. 20, 1938. F. M. SLATER 2,140,654 GLAMIPINGDEVICE I Filed May 18, 1957 l--ffl/ 30 y n j'. f) I INVEITI'ORv H IS ATTORNEY' Patented Dec. 20, 1938 UNITED STATES PATENT OFFICE CLAMPING DEVICE Application May 18, 1937, Serial No. 143,283

1 Claim.

This invention relates to supporting devices, and more particularly to a clamping device for securing a pneumatically fed rock drill to a supporting element, as for example a quarry bar or a column.

One object of thevinvention is to enable the rock drilling mechanism; to be conveniently and quickly adjusted with respect to the supporting element and the work.

Another object is to enable the clamping device to accommodate drilling mechanisms of different diameters.

Other objects will be in part obvious and in part pointed out hereinafter.

In the drawing accompanying this specification and in which similar reference numerals refer to similar parts,

Figure 1 is a side elevation of a clamping device constructed in accordance with the practice of the invention and rock drilling mechanism and its support to which it is applied,

Figures 2 and 4 are transverse views taken through Figure 1 on the line 2-2 showing the clamping device applied to elements of different diameters, and

Figure 3 is a transverse view taken through Figure 2 on the line 3 3.

Referring more particularly to the drawing, the clamping device, constructed in accordance with the practice of the invention and designated in its entirety by 20, is shown in gripping engagement with a rock drilling mechanism 2| and supported by a cross arm 22 which, in turn, is supported by a column 23.

'I'he column 23 may be of a well known type comprising a tubular member 24 carrying a foot piece 25 having pointers 26 to engage the supporting material 21, as for example the floor of a drift. A screw 28 is threaded into the upper end of the column to apply the pressure required for pressing the pointers 26 into the floor 21 and to force a pointer 29, carried by the screw 28, into engagement with the roof 30 of the drift.

The cross arm 22 may be provided with suitable devices (not shown) for aiiixing it to the tubular member 24 and to enable it to be adjusted longitudinally thereof. The arm may be of any suitable length and serves as a support for a clamp 3| which is secured to the arm by a yoke 32 and bolts 33 extending through the yoke and threaded into the clamp 3 I.

'I'he clamp 3| is of known design comprising an integral jaw 34 and a movable jaw 35 which is pivotally connected to the clamp 3| and clamp- 31 extending through the jaw 35 and threaded to the clamp 3|. The jaw 34 is recessed to receive a cone 38 of the clamping device 20 and the jaw 35 is constructed to engage the conical surface of the cone 38.

The cone 38 constitutes an integral portion of a jaw 39 which, together with the cone 38, forms the base member of the clamping device 20. The interior of the jaw 39 is in the form of a concave recess 40 which extends longitudinally of the jaw 39 and on the upper surface and the opposite sides of the jaw 39 are lugs 4| and 42.

'I'he lugs are arranged in pairs. Those designated 42 support a pivot pin 43 for a jaw 44 having a concave recess 45 which, together with the recess 40, defines an opening between the jaws to receive rock drilling mechanism 46. The lugs 4| also support a pin 41 which extends through the eye of a bolt 48 lying in a slot 49 in the free end of the jaw 44. A nut 50 threaded on the bolt 48 and seating on a ilat surface 5| on the jaw, has a handle or lever 52 whereby it may be manipulated to clamp the jaws 44 and 39 together.

Although the clamping power for holding the rock drilling mechanism 46 in the correct position with respect to the work is applied through the jaws 39 and 44 they do not directly engage the rock drilling mechanism. They are, instead, provided on their inner surfaces with lugs 53 to accommodate pivot pins 54 of which the ends extend exteriorly of the lugs 53 and into end walls 55 of gripping members 56. Preferably only three gripping members 56 are employed, as by arranging one on the jaw 44 and two on the jaw 39.

In the outer surfaces of the gripping members 56 are recesses 51 to accommodate the lugs 53 and the inner ends of the gripping members are in the form of concave surfaces 58 to engage the element intended to be gripped, in this instance the cylinder 59 of the pneumatic feeding mechanism of a rock drill 6U. The curvature of the concave surfaces 58 may be selected to conform to that of a feeding mechanism of a given diameter and the said surfaces are interrupted by slots or spaces 6| which open into the recesses 51 so that actually two longitudinally extending gripping surfaces are presented by each .gripping member. In this way the gripping portions of the members 56 will be capable of accommodating feeding mechanisms of different diameters.

In practice, this has been found to be highly convenient for the reason that the dimension of rock drilling mechanisms of different manufacture often vary. By thus rendering the clamping device capable of accommodating feeding mechanisms of different sizes the necessity of maintain- It is moved toward and removed from the Work devices.

by pressure fluid admitted into the cylinder 59 of the feeding mechanism in a well known manner. For simplicity of illustration the rock drill 6D is arranged in a horizontal plane. It is to be understood, however, that it may be otherwise positioned, as for example by inclining it above or below the horizontal and this may be accomplished by releasing the yoke 32 and swinging the clamp 3| about the cross arm 22.

In the operation of the device, wheneverit is intended to placethe rock drilling mechanism in a desired position with respect to -the work, the various clamping elements, as for example the yoke 32, the jaw 35 and the yoke 32 are loosened to permit the clamp 3| to swing about'the axis of the arm 22 and the clamping device 20 to rotate within the jaws 34 and 35. The rfeeding mechanism of the rock drill may then be placed between the gripping members 56 and the various elements be rotated, as required, to bring the cutting end of the working implement to a desired position on the rock face. Thereafter the bolts 33 may again be tightened to clamp the yoke and, therefore, the clamp 3| securely to the arm 22. The jaw 35 is then tightened to clamp the cone 38 xedly to the clamp 3| after which the nut 50 is manipulated to clamp the gripping members into firm gripping engagement with the cylinder 59. The rock drill will then be in readiness for a drilling operation and will be held rmly in the desired position by the various clamping VI claim:

v `In a clamping device, a lower jaw provided with a conical base'having a central opening therethrough, lugs on either side of said opening integral with said lower jaw adapted to act as pivotal supports, an upper jaw having curved inner and outer surfaces, a pivot to secure one end of said lower jaw to one end of said upper jaw, a lug protruding from the inner surfaceV of said upper jaw tol act as a pivotal support and defining recessesxon the inner surface of said jaw on either side thereof, a bolt pivotally connected to the free end of said lower jaw, a nut for the bolt, and a seat formed above a recess in thefree end of the upper-'jaw to support the nut when the pivotal bolt-is placed in said recess to clamp the jaws together. f

FRED M. SLATER. 

